Conventionally, as the above-mentioned seat control system, there has been proposed a seat control system shown in FIG. 5, for example. As shown in the drawing, the conventional seat control system 100 includes: a plurality of motors M which form loads disposed on respective seats of a vehicle; a control ECU 101 for controlling these motors M; and a wire harness W connected between the control ECU 101 and the motors M.
The wire harness W is branched in plural corresponding to the respective seats, and a connector C10 is mounted on respective terminals of branched wire harnesses. The plurality of motors M disposed on the respective seats is connected to the connector C10. In the connector C10, a communication circuit capable of performing multiplex communication with the control ECU 101, a drive circuit for driving the motors M and a sensor circuit for detecting drive amounts of the motors M are incorporated (none of them shown in the drawing).
The communication circuit incorporated in the connector C10 performs communication with the control ECU 101, and drives the motors M in accordance with commands from the control ECU 101. The connector C10 is also connected to switches for operating the motors M, and outputs operation signals of the switches to the control ECU 101. The control ECU 101 performs a control of the respective motors M based on the operation signals.
As described above, the connector C10 relays the communication between the control ECU 101 and the plurality of motors M and hence, it is unnecessary to respectively establish connection between the respective motors M and the control ECU 101 thus enhancing wiring property of the wire harness W and suppressing the increase of a weight of the wire harness W.
The seat control system 100 described above is an effective means for relaying signal levels. In driving electric loads such as the motors M or the like as described above, however, it is necessary to incorporate the drive circuit and the censor circuit in the connector C10 and hence, the connector C10 becomes large-sized thus giving rise to a drawback that mountability of the seat control system is lowered. Further, it is necessary to change the specifications of connectors in conformity with the specifications of loads mounted on a vehicle thus also giving rise to a drawback that the standardization of the seat control system becomes difficult.